Android自动手绘,Android实现手绘功能

本文实例为大家分享了Android实现手绘功能的具体代码，供大家参考，具体内容如下

布局文件如下

xmlns:app="http://schemas.android.com/apk/res-auto"

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

tools:context="com.example.administrator.main.DrawActivity">

android:id="@+id/iv"

android:layout_width="1200px"

android:layout_height="1500px"

android:layout_alignParentLeft="true"

android:layout_alignParentRight="true"

android:layout_alignParentStart="true" />

android:id="@+id/linearLayout4"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_alignParentBottom="true"

android:layout_gravity="center_horizontal"

android:orientation="horizontal">

android:id="@+id/btn_resume"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_alignParentBottom="true"

android:layout_alignParentEnd="true"

android:layout_marginEnd="79dp"

android:text="重绘" />

android:id="@+id/btn_save"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_alignBottom="@+id/linearLayout4"

android:layout_marginStart="91dp"

android:layout_toEndOf="@+id/linearLayout4"

android:text="保存" />

Activity代码如下，其中线的颜色，宽度等属性都可以修改。

package com.example.administrator.main;

import android.content.Intent;

import android.graphics.Bitmap;

import android.graphics.Canvas;

import android.graphics.Color;

import android.graphics.Paint;

import android.net.Uri;

import android.os.Environment;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.view.MotionEvent;

import android.view.View;

import android.widget.Button;

import android.widget.ImageView;

import android.widget.Toast;

import java.io.File;

import java.io.FileOutputStream;

public class DrawActivity extends AppCompatActivity {

private ImageView iv;

private Bitmap baseBitmap;

private Button btn_resume;

private Button btn_save;

private Canvas canvas;

private Paint paint;

float radio;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_draw);

radio = 10;

iv = (ImageView) findViewById(R.id.iv);

// 初始化一个画笔，笔触宽度为5，颜色为红色

paint = new Paint();

paint.setStrokeWidth(radio);

paint.setColor(Color.BLACK);

iv = (ImageView) findViewById(R.id.iv);

btn_resume = (Button) findViewById(R.id.btn_resume);

btn_save = (Button) findViewById(R.id.btn_save);

btn_resume.setOnClickListener(click);

btn_save.setOnClickListener(click);

iv.setOnTouchListener(touch);

}

private View.OnTouchListener touch = new View.OnTouchListener() {

// 定义手指开始触摸的坐标

float startX;

float startY;

@Override

public boolean onTouch(View v, MotionEvent event) {

switch (event.getAction()) {

// 用户按下动作

case MotionEvent.ACTION_DOWN:

// 第一次绘图初始化内存图片，指定背景为白色

if (baseBitmap == null) {

baseBitmap = Bitmap.createBitmap(iv.getWidth(),

iv.getHeight(), Bitmap.Config.ARGB_8888);

canvas = new Canvas(baseBitmap);

canvas.drawColor(Color.WHITE);

}

// 记录开始触摸的点的坐标

startX = event.getX();

startY = event.getY();

break;

// 用户手指在屏幕上移动的动作

case MotionEvent.ACTION_MOVE:

// 记录移动位置的点的坐标

float stopX = event.getX();

float stopY = event.getY();

Thread t = new Thread(new Runnable() {

@Override

public void run() {

radio += 0.1;

try {

Thread.sleep(1000);

} catch (InterruptedException e) {

e.printStackTrace();

}

}

});

t.start();

paint.setStrokeWidth(radio);

//根据两点坐标，绘制连线

canvas.drawLine(startX, startY, stopX, stopY, paint);

// 更新开始点的位置

startX = event.getX();

startY = event.getY();

// 把图片展示到ImageView中

iv.setImageBitmap(baseBitmap);

break;

case MotionEvent.ACTION_UP:

radio = 5;

break;

default:

break;

}

return true;

}

};

private View.OnClickListener click = new View.OnClickListener() {

@Override

public void onClick(View v) {

switch (v.getId()) {

case R.id.btn_save:

saveBitmap();

break;

case R.id.btn_resume:

resumeCanvas();

break;

default:

break;

}

}

};

/**

* 保存图片到SD卡上

*/

protected void saveBitmap() {

try {

// 保存图片到SD卡上

String fileName = "/sdcard/"+System.currentTimeMillis() + ".png";

File file = new File(fileName);

FileOutputStream stream = new FileOutputStream(file);

baseBitmap.compress(Bitmap.CompressFormat.PNG, 100, stream);

Toast.makeText(DrawActivity.this, "保存图片成功", Toast.LENGTH_SHORT).show();

// Android设备Gallery应用只会在启动的时候扫描系统文件夹

// 这里模拟一个媒体装载的广播，用于使保存的图片可以在Gallery中查看

Intent intent = new Intent();

intent.setAction(Intent.ACTION_MEDIA_MOUNTED);

intent.setData(Uri.fromFile(Environment

.getExternalStorageDirectory()));

sendBroadcast(intent);

} catch (Exception e) {

Toast.makeText(DrawActivity.this, "保存图片失败", Toast.LENGTH_SHORT).show();

e.printStackTrace();

}

}

// 手动清除画板的绘图，重新创建一个画板

protected void resumeCanvas() {

if (baseBitmap != null) {

baseBitmap = Bitmap.createBitmap(iv.getWidth(),

iv.getHeight(), Bitmap.Config.ARGB_8888);

canvas = new Canvas(baseBitmap);

canvas.drawColor(Color.WHITE);

iv.setImageBitmap(baseBitmap);

Toast.makeText(DrawActivity.this, "清除画板成功，可以重新开始绘图", Toast.LENGTH_SHORT).show();

}

}

}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。